Conventional alkaline cells generally include a steel cylindrical can having a cathode comprising manganese dioxide as the active material and formed on the interior surface of the steel can, an anode comprising zinc powder as the active material and located in the center of the cell, a separator located between the anode and the cathode, and an alkaline electrolyte solution simultaneously contacting the anode, cathode, and the separator. A conductive current collector is commonly inserted into the anode active material and a seal assembly provides closure to the top end of the steel can.
A goal in designing alkaline batteries is to increase the discharge efficiency of the zinc when the battery is discharged at a high drain rate. In conventional batteries, the discharge efficiency of the zinc is generally low when the battery is discharged at a high rate. For example, alkaline batteries currently on the market utilize only approximately 20-30% of the zinc in the cell when the cell is discharged at a high drain rate.
Electrochemical cell manufacturers and consumers desire an electrochemical cell with better performance, and therefore, there is an ongoing need for better performing electrochemical cells that are low in cost. One way to achieve better performance of an electrochemical cell is to increase the zinc utilization.
The present invention improves the discharge service performance, especially at a high drain rate, of an electrochemical cell by the inclusion of elemental sulfur in the anode of the cell.
One aspect of the present invention is an electrochemical cell comprising an alkaline electrolyte and an anode having an electrochemically active material and elemental sulfur.
Another aspect of the present invention is a method of constructing an electrochemical cell comprising the steps of providing a cathode, an alkaline electrolyte, and an anode, and adding elemental sulfur to the anode.
These and other features, advantages and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims, and appended drawings.